A known contact element of this type is stamped from a sheet metal strip and rolled to form a substantially cylindrical contact element. One end of the contact element is provided with a terminal portion having tabs for establishing electrical contact with the conductors of a wire by deforming the tab around the end of a conductor. At its other end, the contact member is provided with a contact portion in the form of a tubular pin. The locking portion of the contact element is provided with two stamped, tongue-shaped locking fingers which extend outwardly under an acute angle relative to the longitudinal axis of the contact element. After the conductor has been connected to the terminal portion of the contact element, the forward contacting portion is first pushed into the chamber of an insulating housing. The locking fingers are urged radially inwardly at a constricted passage point inside the chamber. Once the locking fingers have passed beyond the constricted region, they snap radially outwardly and prevent the contact element from being inadvertently removed. In this position the locking fingers absorb the entire pulling force which is exerted upon the contact element via the conductor. In the case of a strong tensile load, the locking fingers, which usually are bent slightly outwardly, are deflected toward the interior of the contact element and permanently distorted. Thus, the contact element is no longer kept in the proper axial position, and the damaged contact element must be replaced. In the case of very small contact elements with contact pins having a size of, say, 1.6 mm, the thickness of the sheet metal can amount to about 0.3 mm only. Therefore, it is not possible to increase the stability of the locking fingers by using sheet metal of greater thickness.